Soviet cosmonaut Valentina Tereshkova became the first woman to fly into space in 1963. But it would be nearly two decades before another lady left Earth’s atmosphere.

NASA opened the space program to female applicants in 1978. Five years later, Sally Ride launched with the seventh Space Shuttle mission, becoming the US’s first woman in space.

She helped pave the way for femmes like Judith Resnik and Christa McAuliffe (who died in the 1986 Challenger explosion), as well as Kathryn Sullivan (the first American woman to walk in space) and a growing number of female explorers around the world.

But it’s ridiculous to think that, in the nearly 60-year history of sending humans to space, no two women have ever embarked on a spacewalk together—even coincidentally.

Better late than never, though.

Koch and McClain’s seven-hour spacewalk will be broadcast on NASA TV later this month.

The pair, along with Hague, were members of NASA’s 2013 astronaut class, which consisted of 50 percent women.